android 蓝牙avrcp功能的实现

Android 蓝牙AVRCP功能的实现

作者:Macro Liu

AVRCP的按键定义:

\sdk\emulator\keymaps\AVRCP.kl

key 200 MEDIA_PLAY_PAUSE WAKE

key 201 MEDIA_PLAY_PAUSE WAKE

key 166 MEDIA_STOP WAKE

key 163 MEDIA_NEXT WAKE

key 165 MEDIA_PREVIOUS WAKE

key 168 MEDIA_REWIND WAKE

key 208 MEDIA_FAST_FORWARD WAKE

BCM(broadcom)宏定义需要打开:

BOARD_HAVE_BLUETOOTH_BCM := true

BT音频控制的代码

external\bluetooth\bluez\audio\control.c

(1) 按键的MAP

static struct {

const char *name;

uint8_t avrcp;

uint16_t uinput;

} key_map[] = {

{ "PLAY",PLAY_OP,KEY_PLAYCD },

{ "STOP",STOP_OP,KEY_STOPCD },

{ "PAUSE",PAUSE_OP,KEY_PAUSECD },

{ "FORWARD",FORWARD_OP,KEY_NEXTSONG },

{ "BACKWARD",BACKWARD_OP,KEY_PREVIOUSSONG },

{ "REWIND",REWIND_OP,KEY_REWIND },

{ "FAST FORWARD",FAST_FORWARD_OP,KEY_FASTFORWARD },

{ NULL }

};

(2) 按键处理

static void handle_panel_passthrough(struct control *control,

{

…

for (i = 0; key_map[i].name != NULL; i++) {

uint8_t key_quirks;

if ((operands[0] & 0x7F) != key_map[i].avrcp)

continue;

DBG("AVRCP: %s %s", key_map[i].name, status);

key_quirks = control->key_quirks[key_map[i].avrcp];

if (key_quirks & QUIRK_NO_RELEASE) {

if (!pressed) {

DBG("AVRCP: Ignoring release");

break;

}

DBG("AVRCP: treating key press as press + release");

send_key(control->uinput, key_map[i].uinput, 1);

send_key(control->uinput, key_map[i].uinput, 0);

break;

}

send_key(control->uinput, key_map[i].uinput, pressed);

break;

}

…

}

HCIDUMP数据分析

以Sony耳机DRC-BT15为例

#adb shell

#hcidump –X

左键:

> ACL data: handle 12 flags 0x02 dlen 12

??? L2CAP(d): cid 0x0042 len 8 [psm 0]

????? 0000: 30 11 0e 00 48 7c 4c 00?????????????????????????? 0...H|L.

< HCI Command: Exit Sniff Mode (0x02|0x0004) plen 2

? 0000: 0c 00???????????????????????????????????????????? ..

< ACL data: handle 12 flags 0x00 dlen 12

??? 0000: 08 00 4b 00 32 11 0e 09? 48 7c 4c 00????????????? ..K.2...H|L.

> HCI Event: Max Slots Change (0x1b) plen 3

? 0000: 0c 00 05??